I've never seen this before but I have a strong scotch ale that is still producing a significant amount of CO2 24 days after pitching the yeast. OG was 1.077. I used two packages of Wyeast 1338 European Ale each in a 500mL starter. This is the first that I've used this yeast so this may be expected by someone else. Anyone else experience this before?

Did you take a gravity reading? There is a high probability that the bubbles are just from offgassing co2 coming out of solution. If its still fermenting, the only way to tell is to take a hyrdo reading. On a side note, how does it smell?

I haven't checked the gravity on this yet. I was going to keep it in primary for at least 30 days anyway so I haven't taken a reading but was really expecting the bubbling to stop by now. I've heard the co2 leaving the solution theory before but I don't quite get that. If the co2 was already in the solution then the pressure wouldn't be increasing causing a bubble right? Oh, just realized that this could have been misunderstood. This is bubbling in the airlock. Also, I wrote a while back about another oddity with this beer that I hadn't seen before. The inner-most tube of the 3-piece airlock has water in it. I can actually see the bubbles coming up the tube. It causes a foam in the airlock. Here's a picture:

I have experienced the bubbling airlock for 25 days or so, I asked around here and the general consensus was off-gassing. Having said that, I took a gravity reading at 20 days and had about 1.020, my OG was 1.060. I decided to give the fermenter a good swirl let it warm up to about 70 degrees and wait a week. 25 days out I still had bubbles in my airlock. I said F it and bottled exactly 28 days (4 weeks from pitching), when I took my gravity reading it was 1.018. I understand how outgassing may happen, but my estimated FG was 1.015. This was an extract brew, so I don't think the gravity was gonna drop any further. At any rate, yes, I have experienced a "long" fermentation. This was my 3rd brew and the other two quit bubbling within 7 days so I was a little uneasy about this brew creating bottle grenades. I am glad I swirled, warmed and waited I think it was worth it. IMHO (bear in mind I am no expert and still pretty new to this) I think sometimes it just takes a while. My yeasties must have got drunk off the brew and taken a siesta!

I brewed a belgian strong ale recently and it bubbled in primary and secondary for probaby around 6 weeks. I was in the same boat as you though, planning 2 months before bottling so i did not take any gravity readings in between. It seemed to me like there was still fermentation going on since it really gradually tapered off.

it wasnt a misunderstanding. As ambient temperature changes, co2 will come out of solution and cause the airlock to move. When i come down in the morning to check my beers, i have liquid in the inner tube which is indicative of a temperature change which in turn caused a pressure change. Take a gravity reading and post back....And just to give you some idea, i still have pressure in my airlock with bubbles occasionally on a trappist i have had sitting for 6+ months.

Ok. It's been 36 days now. I took two gravity readings 3 days apart and it's not moving. The beer is at 1.037. I've heard of strong scotch ales having FG higher than 1.040 but they probably had higher OG. According to Wyeast the low end of attenuation should have been 67% which would be a FG of 1.026 so I'm way off that. Should I add beano, go ahead and bottle it, leave it on the yeast? I have roused the yeast and increased the temperature slowly. The airlock isn't bubbling anymore by the way.